1. Field of the Invention
The present invention relates to gas burner attachments and particularly to a wok support ring which straddles a stovetop grate and a flame concentrating ring with an inwardly curved upper wall portion and air inlet vents at its base for encircling a gas burner and directing the flames upwardly and inwardly to the focus on the bottom center of a wok.
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
The development of the traditional wok by the Chinese over 2,500 years ago was necessary from the tough living conditions in China. Scarce supply of firewood forced the frugal Chinese to devise the present day methods of flash-flame cooking or better known as stir-fry.
The stir-flying technique involves the use of a Chinese wok, which usually requires cooking of vegetables and meats for very short time periods at high heat. In a typical stir-fry recipe, the cooking time is three to five minutes, or less. The health benefits of short-time cooking with minimal use of fats are substantial. Less fat is absorbed by the food being cooked in a wok than with western methods and resulting fat intake by the consumer is at a minimum. In addition to the health benefits, the flavor of the food, particularly vegetables, is substantially retained by the high heat searing of the food surfaces.
Chinese restaurants can attain these high temperatures by using commercial burners that reach over 200,000 BTU's (British Thermal Units). The typical American gas stove burner outputs an average 7,000 to 15,000 BTU's maximum. The commercial burners are able to bring the surface temperature of the wok to over 700 degrees F. to impart what the Chinese experts says is the elusive “Wok Hay”. “Hay”, the Cantonese Chinese pronunciation, or “chi” or “qi”, the Mandarin Chinese pronunciations (the ones most familiar to the non-Chinese reader), is breath—the Chinese concept of vital energy that flows through the body. Chinese chefs stress Wok Hay must be achieved on the surface of the wok as the primary directive, this is not an issue for Chinese restaurants.
For stovetop cooking on a gas jet home stove, Wok Hay is quite elusive because of the insufficient amount of BTU's generated by the average domestic gas stove. This has given rise to a number of innovative wok designs in addition to the traditional cast-iron or stamped carbon steel woks that have entered the market. Today's Asian woks are manufactured in stainless steel, flat bottom, layered-steel/aluminum/steel, aluminum Teflon coated and electric/Teflon bottom. These types of woks have lured cooks away in the past, however, many devotees are returning to the faithful old cast iron or stamped carbon steel wok, because they respond most readily to changes in heat. Their thin gauge allows less time to heat up in preparation for cooking. Most commercially available Asian woks address certain aspects; heating, convenience and utility, however, they all are band-aids and miss their mark on the biggest issue in wok cooking: hi-temperature heat or Wok Hay.
Present day conventional gas stove burners are designed to take on all types of currently mass produced cookware. Practically all cookware is flat bottomed in nature. The typical western style stove burner emits a flame that fans outwardly as a pot or pan is placed on it. This design is most effective because it takes advantage of the entire flat surface area of the cookware.
In the case of the Asian wok, it's the opposite. The wok's unique round bottom causes the flame from a typical stovetop gas jet to mushroom out to its edges. This is an inherent design flaw against the wok. The wok and the conventional stovetop jet burner are not a compatible match.
One of the main problems with the use of the wok in Western kitchens is that it does not adapt well on electric and gas ranges. The wok was developed for use by placing it directly on rings with a wide based fire built underneath. However, the cooking surfaces utilized, particularly in the west, are typically flat for delivering heat to flat bottomed cooking vessels such as frying pans or sauce pans. The round dome surface of the wok does not adapt well to cooking on modern electric and gas ranges. Various methods have been utilized in attempts to overcome this problem.
One method involves modifying the structure of the wok itself. The production of flat bottomed woks for resting in a stable manner on a flat range top, has been done either by making the wok wall a uniform thickness and having both inside and outside have a flat bottom, in which case the wok is a little more than a high sided frying pan with all its inherent disadvantages, or by building the outside of the wok up only to leave a spherical cooking surface with a flat exterior surface. The disadvantage of this method is the cooking technique in spatula manipulation, i.e., movement of a metal spatula from a round surface to a flat plane. This can be discerning to those more accustomed to round bottomed woks. Flat bottomed woks do not permit the sweeping, surface-scooping motion of the round-edged spatulas used in wok cooking; where rapid, fluid motions are essential for effective stir-frying; and, flat bottomed woks do not permit the user to rock the wok smoothly over the heating surface in order to efficiently spread other ingredients to the food being cooked in the wok while keeping the wok in full contact with the heating surface. The other disadvantage of this method is that the weight and mass of the wok is increased.
Another modification to the wok has been the use of electric woks wherein the heating elements are arrayed in a partially spherical design at the bottom of the wok to provide even heat distribution. These woks are typically quite expensive and have the same disadvantages as the flat bottomed wok's unwieldiness. Their heat control thermostats are not sensitive enough for the quick temperature changes stir-frying demands. Another disadvantage to electric woks is that most of them are Teflon coated, which give rise of potential health issue associated with the inhaling of toxic fumes when the surface temperature exceeds 450 degrees F.
Those who wish to attain the advantage of cooking in a traditional thin walled wok have been forced either to abandon the use of modern ranges or else to utilize some form of interface adapter between the range and the wok. The alternate heating methods are less than desirable since they force the user to abandon the range top, the most commonly used cooking area in the kitchen. Thus, interface adapters have become popular.
The interface adapters manufactured to date have been rings or collars which are adapted to fit on the range element surface to provide a circular ring upper surface into which the wok bottom nests in a fairly stable fashion. Their lack of stability is a major disadvantage to prior art interface adapters.
Electrical range elements are typically spiral elements with spaces between different portions of the element. In this manner, the bottom surface of the adapter ring will typically rest partially on the element and partially on the spans between portions of the element. Since the shape and size of the electrical elements varies drastically from stove to stove, this can often result in an unstable circumstance. Instability can be a great disadvantage since spillage of cooking oil can lead to kitchen fires and severe burns to the user.
The problem is even more notable in gas ranges which typically have only an open latticework frame to support the cooking vessel with wide spaces between the various elements of the frame. There is a greater danger of instability of the adapter rings on this sort of latticework than even on the electrical elements.
Another disadvantage of prior art adapter rings or collars is that the heat is delivered to the wok in an uneven fashion. Thermal energy is delivered directly by conduction to the ring portion of the wok where the top of the adapter ring and the wok directly interface. However, the remaining portions of the wok must either be heated by radiant energy or by indirect conduction. Consequently, a hot ring area may develop part-way up the sides of the wok, particularly if the wok is constructed of less than optimal material. This provides for uneven cooking and does not provide the maximum heat to the very bottom of the wok where most of the actual cooking takes place.
In summary, a regular home stovetop gas jet burner normally spreads flames outwardly away from the center to cover a large area on a flat pan, which is not effective for a wok which needs a very hot flame in the bottom center of the wok, and ordinary home stoves are unsatisfactory for supporting spherical bottoms of Asian wok cooking vessels.
While a number of prior art wok supports have been attempted to be used with gas burners on stove tops (as well as some for use with electric coils) and a number of rings of various types for focusing flames of stovetop gas burners, none of the prior art patents provide a ring for focusing gas jet stovetop burners in combination with a universal wok support to fit a wide variety of stovetop grates and suspend a wok an effective distance above the gas jet to receive the full effect of the focused gas jet on the bottom center of the wok.
U.S. Pat. No. 5,775,316, issued Jul. 7, 1998 to Jones, describes a cooking range with interchangeable grate and wok ring mounted thereon. The range supports the wok ring and the grate over a gas fired burner element. The grate and the wok ring include a support plate which selectively engages the cooking range in a preferred orientation. The wok ring includes a preferred configuration of the support ring.
U.S. Pat. No. 5,345,062, issued Sep. 6, 1994 to Maudal, discloses a support stand which adapts an Asian WOK to a Western kitchen range. The stand provides an upper ring to receive a round bottomed WOK; the ring has sufficient diameter to accommodate the WOK securely in the stand. The base of the stand adapts to prior art drip pans placed in heating wells, where the well has gas or electrical heating elements located according to the type of range, and thus anchors the stand to the kitchen range top. A second concept modifies existing drip pans to provide both the functions of drip pan and support stand in a single, combined support stand. This stand replaces existing stands and drip pans and anchors the WOK to the kitchen range top. A third concept converts a prior WOK fire ring into a trivet allowing use of the WOK at a dinner table.
U.S. Pat. No. 6,718,967, issued Apr. 13, 2004 to Luther, claims a wok support for use in a wok range which incorporates a refractory insulating material into its structure. The wok support includes a tubular support structure having internal space in its wall. The refractory insulating material is disposed in the internal space.
U.S. Pat. No. 5,315,983, issued May 31, 1994 to Law, indicates a wok support ring comprising a two-piece support ring structure for supporting a wok cooking vessel on top of a burner cylinder of a cooking range. The structure features two components: a top ring of a substantially circular shape upon which sits a wok; and a base ring having a substantially circular shape that removably rests on the burner cylinder. The top ring removably rests on the base ring. The base ring itself comprises a first ring and a first mating means disposed on top of the first ring for removably coupling the base ring to the top ring. The top ring comprises a second ring upon which sits the wok and a second mating means projecting from the bottom of the second ring for removably coupling the top ring to the first mating means. The base ring further comprises a third mating means for removably coupling the base ring to the burner cylinder.
U.S. Patent Application #20020162923, published Nov. 7, 2002 by Geddes, indicates a support for a cooking vessel which comprises a ring having an upper portion for supporting the cooking vessel, and a lower portion formed with L-shaped slots for bayonet-type engagement with tines of a pan support grid of a conventional gas hob.
U.S. Pat. No. 4,607,613, issued Aug. 26, 1986 to Toldi, puts forth a wok adapter made from a thermally conductive material and has an exterior shape substantially in the nature of a frustum of a cone. The upper surface of the adapter is concave in the shape of a sector of a sphere such that a traditional wok will nest therein with approximately equal contact over the entire interface therebetween. The bottom surface of the adapter is substantially flat for maintaining a solid stable perch on either electrical stove elements or gas range lattice support structures. The bottom of the adapter may be provided with anti-slip protrusions which prevent the adapter from sliding on the top of the range element. The side of the adapter is angled outward in a conical fashion such that the heat generated by a smaller area of element at the bottom surface of the adapter may be delivered to a greater area of the wok surface for maximum usable cooking area. The adapter can be provided with a handle attachment detent such that a detachable handle may be attached thereto for transporting the adapter while it is still hot.
U.S. Pat. No. 6,093,018, issued Jul. 25, 2000 to Avshalumov, shows a gas burner comprising in combination means for controlled feeding and subsequent admixing of a secondary air directly to the base of the flame in a form of a cap coaxially surrounding a burner head of the gas burner comprising a lateral apertures for issuing combustible air-gas mixture to form a flame. The through lateral openings of the predetermined size having the total cross section greater than the total cross-section of the apertures of burner head are performed on the side wall surface of the cap. During the operation of the gas burner the exact measured amount of the secondary air is admixed directly to the base of the flame, thereby highly efficient and complete combustion process characterized by high-elevated temperature is achieved.
U.S. Pat. No. 698,507, issued Apr. 29, 1902 to Jeha, discloses a gas saving appliance for concentration heat to the bottom of a cooking utensil. The appliance comprises an annular ring body with a flanged upper edge that leaves a heat concentrating opening at the top. The ring body is provided with ventilation holes.
U.S. Pat. No. 834,733, issued Oct. 30, 1906 to Jeha, puts forth a gas saving appliance which comprises an inner cylindrical perforated drum which direct the gas heat upwardly and an outer inwardly curved and perforated drum with an opening at its top which allows heat to contact the bottom of a cooking vessel.
U.S. Pat. No. 5,791,333, issued Aug. 11, 1998 to Bennett, claims a burner system for a gas range which includes an annular metal pan through which the gas flame selectively projects, and an annular grill or grate overlying the pan on which the bottom of a cooking utensil is selectively supported. In addition, the inventive system includes an element for directing the gas flame inwardly and upwardly towards the bottom of the utensil, as well as for substantially reducing heat loss generated by flame operation.
U.S. Pat. No. 1,346,761, issued Jul. 13, 1920 to Moore, claims a gas burner with a frusto-conical cover for directing the flames through the center upper orifice. The cover has air inlet notches at its base and a plurality lateral flame emitting orifices in the side wall.
U.S. Pat. No. 1,414,146, issued Apr. 25, 1922 to Moellendick, describes a gas burner attachment for retaining and directing heat to the bottom of a pan. The device is made of a strip of sheet metal with notches at the bottom edge thereof for the purpose of receiving the arms of a gas burner.
U.S. Pat. No. 1,546,919, issued Jul. 21, 1925 to Dore, puts forth a heat saving device for a gas burner. The device comprises an annular upwardly converging wall or deflector forming a converging flame directing passage communicating with an unobstructed upper central flame discharge opening. The deflector is supported on the burner by four internally located downwardly converging support arms.
U.S. Pat. No. 1,592,729, issued Jul. 13, 1926 to Feist, concerns an adjustable economizer and adapter for burners having a annular wall with an upwardly converged top flange for the purpose of focusing the heat to the bottom of the cooking vessel.
U.S. Pat. No. 1,692,000, issued Nov. 20, 1928 to Steffens, illustrates a mantle which sits upon gas burners. The mantle comprises an inverted frusto-conical, the lower wider opening of which sits on top of the burner and directs the heat up through the upper narrower opening. A cylindrical portion is affixed the upper narrower opening to further direct the heat through a stove top grate.
U.S. Pat. No. 1,772,407, issued Aug. 5, 1930 to Wilhelm, shows a gas burner attachment which comprises an auxiliary top having an elevated plateau with a gently sloping downward flange provided with a plurality of circumferentially arranged air vent opening and a centrally located depressed portion to ensure complete combustion.
U.S. Pat. No. 1,072,115, issued Sep. 2, 1913 to Harmon, is for a gas stove having a housing positioned over the burner to confine the flame against the bottom of a cooking vessel, said housing having notches in its upper edge for receiving the utensil holding fingers of the stove top.
U.S. Pat. No. D250,931, issued Jan. 30, 1979 to Pierce, provides the ornamental design for a gas saving grate.
U.S. Pat. No. D364,534, issued Nov. 28, 1995 to Brown, puts forth the ornamental design for an adapter for elevating an accessory above a stove heating element.
U.S. Pat. No. D545,124, issued Jun. 26, 2007 to Hawkins, is for the ornamental design for a wok ring.
U.S. Pat. No. 4,006,676, issued Feb. 8, 1977 to Adamis, discloses a crepe-making pan and support. The crepe pan is such that it is adapted to distribute the batter over the flat exposed bottom surface of the bottom of the pan; a base locates and supports the pan in position and is so dimensioned as to surround the flame and distribute the heat evenly over the flat bottom of the pan; the weight distribution of the pan and its handle being such that the pan will be firmly seated around a suitable flange on a shoulder adjacent the flange of the substantially cylindrical base.
U.S. Pat. No. 4,448,186, issued May 15, 1984 to Smith, concerns a device for concentrating heat from a flame of a gas stove in combination with a cooking utensil includes a first collar rigidly attached to the cooking utensil and mating with a second collar attached to a grid of the stove. The collars may have several peripherally disposed vents. The second collar can be rotated to align the vents and control the venting of the flame of the stove.
U.S. Pat. No. 881,199, issued Mar. 10, 1908 to Palmer, illustrates a stove ring made from a band of light sheet metal. The sheet metal band has vent openings.
U.S. Pat. No. 983,413, issued Feb. 7, 1911 to Swafford, concerns a heat concentrating ring for gas or vapor stoves or ranges of which the height and diameter are adjustable. The device comprises two ring form sections, one having horizontally elongated slots and the other having vertically elongated slots and fasteners, such as bolts passing through the slots. One of the ring forms has additional air supply openings.
U.S. Pat. No. 1,131,226, issued Mar. 9, 1915 to Frank, provides a conico-cylindrical heating device which has an upper opening that supports a cooking vessel and a wider lower opening that sits upon a stove top grate. The device has a support made from intersecting grate bars which extend across the lower opening. Slots in the ends of the grate bars interlock with the outer face of the lower receiver opening.
U.S. Pat. No. 1,142,603, issued Jun. 8, 1915 to Moellendick, shows an ornate gas stove attachment which confines and directs the heat from a burner to the bottom of a pot or pan. The body member has a lower end which extends over a burner. Within the body member is an inner inwardly curved deflector for directing the heat, the upper opening of which has a series of radially spaced projections that disperse the heat evenly on the bottom of the pan.
U.S. Pat. No. 1,431,696, issued Oct. 10, 1922 to Shankland, discloses a ring-type support for cooking utensils made of a hollow body of sheet metal having annular vertical wall provided with a plurality of perforations. The cooking utensil is supported in an upper opening having a series of stepped diameters in the opening for supporting different sized pans.
U.S. Pat. No. 1,471,788, issued Oct. 23, 1923 to Gardner, indicates an adjustable short ring or funnel-type gas burner attachment which confines, condenses and directs the heat to the article being heated. The device is provided with air holes near the lower edge for providing ventilation and assisting in combustion.
U.S. Pat. No. 1,881,606, issued Oct. 11, 1932 to Humphreville, provides a heat conserver sleeve which surrounds a gas burner and directs the heat upwardly to the bottom of a cooking vessel. The sleeve is provided with a plurality of air vents for admission of secondary air to assist in combustion.
U.S. Pat. No. 4,337,752, issued Jul. 6, 1982 to Leounes, describes a heat retaining collar device for reducing lateral heat dissipation from range top heating elements during cooking operations. An integrally-formed annular collar means of generally frusto-conical configuration is adapted to rest atop a range, in surrounding relation to a heating element disposed on said range top. A generally toroidally-shaped pocket of heated air surrounds an item of cookware adjacent its lower portion when such cookware is slideably received within the opening of the collar-like device surrounding the element. A first alternative embodiment has a hollow collar so that a dead air space interiorly of the collar-like device provides an additional thermal barrier. A second alternative embodiment provides a plurality of successively smaller nesting collars to accommodate cookware of differing sizes.
What is needed is a combination fire ring with walls that curve in at the top to focus the flame of a standard stovetop gas jet into an intense jet of flame focused upwardly and inwardly to hit the bottom center of the wok and a wok support which mounts on and straddles the radial cooking vessel support members of the stovetop grate to position the wok over the gas jet to receive the jet of flame on the bottom center of the wok.